1. Technical Field
The present disclosure relates to minimally-invasive surgery. More particularly, the present disclosure relates to methods and apparatus for controlling surgical instruments using a port assembly.
2. Background of Related Art
Surgical techniques and instruments have been developed that allow the surgeon to perform an increasing range of surgical procedures with minimal incisions into the skin and body tissue of the patient. Minimally-invasive surgery has become widely accepted in many medical specialties, often replacing traditional open surgery. Unlike open surgery, which requires a long incision, minimally-invasive procedures, such as endoscopy or laparoscopy, are performed through one or more short incisions, with much less trauma to the body.
In laparoscopic and endoscopic surgical procedures, a small “keyhole” incision or puncture is made in a patient's body, e.g., in the abdomen, to provide an entry point for a surgical access device which is inserted into the incision and facilitates the insertion of specialized instruments used in performing surgical procedures within an internal surgical site. The number of incisions may depend on the type of surgery. It is not uncommon for some abdominal operations, e.g., gallbladder surgery, to be performed through a single incision. In most patients, the minimally-invasive approach leads to decreased postoperative pain, shorter hospital stay, faster recovery, decreased incidence of wound-related and pulmonary complications, cost savings by reducing post-operative care, and, in some cases, a better overall outcome.
Minimally-invasive surgical procedures are performed throughout the body and generally rely on obtaining access to an internal surgical site through a relatively small pathway, often less than one centimeter in diameter, to the surgical site. One method of providing such a pathway is by inserting a cannula and trocar assembly through the skin of the patient. Commonly, to place the trocar-cannula, the penetrating tip of the obturator of the trocar is pushed through the skin and underlying tissue until the distal end of the cannula is within the body cavity. Alternatively, some trocar devices have a blunt obturator for placing the cannula through a previously-made incision. Once the trocar has been properly positioned, the obturator is removed and the cannula is then available as a pathway between the surgical site and the exterior of the patient's body through which the surgeon may introduce the various surgical instruments required to perform the desired procedures. Surgical instruments insertable through a cannula include forceps, clamps, scissors, probes, flexible or rigid scopes, staplers and cutting instruments.
In some procedures, a wall of a body cavity is raised by pressurization of the body cavity to provide sufficient working space at the surgical worksite and/or to allow a trocar to penetrate the body cavity without penetrating an organ within the cavity. The process of distending the abdomen wall from the organs enclosed in the abdominal cavity is referred to as insufflation. During a laparoscopic procedure (endoscopy in the abdominal cavity), insufflation is achieved by introducing an insufflation gas, such as carbon dioxide, nitrogen, nitrous oxide, helium, argon, or the like, through a Veress needle or other conduit inserted through the abdominal wall, to enlarge the area surrounding the target surgical site to create a larger, more accessible work area. The surgeon is then able to perform the procedure within the body cavity by manipulating the instruments that have been extended through the surgical access devices. The manipulation of such instruments within the internal body is limited by both spatial constraints and the need to maintain the body cavity in an insufflated state.
In minimally-invasive surgery, the surgeon does not have direct visualization of the surgical field, and thus minimally-invasive techniques require specialized skills compared to the corresponding open surgical techniques. Although minimally-invasive techniques vary widely, surgeons generally rely on a lighted camera at the tip of an endoscope to view the surgical site, with a monitor displaying a magnified version of the site for the surgeon to use as a reference during the surgical procedure. The surgeon then performs the surgery while visualizing the procedure on the monitor. The camera is typically controlled by an assistant to the surgeon who is scrubbed into the procedure. In most instances, the assistant does not play any other role in the procedure other than to hold and direct the camera so that the surgeon can view the surgical site. The camera assistant may have difficulty understanding the surgeon's intent, requiring the surgeon either to move the camera himself or ask the assistant to redirect the camera.
Multi-function robotic surgical systems are available with laparoscopic camera control. In general, robotic surgical systems are large and bulky, requiring a large amount of space around the patient, and have complex, time-consuming setups. Extensive training time is typically required for surgeons to learn to operate the remotely-controlled, camera-toting devices, and additional specialized training is also typically required for the entire operating room team. The extremely high initial cost of purchasing a robotic surgical system as well as the relatively high recurring costs of the instruments and maintenance can make it prohibitive for many hospitals and health-care centers.